The present invention relates to an unmanned mobile device which, by means of remote control, makes it possible to install signalization spheres on transmission lines"" lightning rod cables, with the line connected, the sweeping of the cable for maintenance purposes, as well as a method for installation of signalization spheres on transmission lines"" lightning rod cables using the device.
The transportation of large blocks of electric power through long distances is done by means of transmission lines that extend several kilometers within countries. Those power lines are lifted by towers that support themselves by means of spands, crossing rivers, railroads, roadways, or other transmission lines, and may reach heights considerably elevated above the ground.
Due to these and other factors that affect the visibility of transmission lines, those lines represent a hazard for aircrafts.
In order to reduce the danger involved, so-called line signals have been developed which, due to their size and color, provide signalization to aircraft operators, alerting them about the presence of rivers, railroads, or other transmission lines. In recent past, line signals have been installed at strategic distances, along transmission line spans that extend between support towers, so that those elements can become more visible to aircraft operators flying nearby.
Although there are a significant number of accidents involving aircraft hitting transmission lines, spherical signals have seldom been used so far, not only due to the high cost involving their installation in existing lines, but mainly because of the difficulty regarding their installation. The difficulty and cost of installation result from the inaccessibility to the installations, the high voltage that they can transmit and the existing and available line signals themselves, which, for the purposes of a faultless installation, require disconnection of the current flow along the lines, and removal of the lightning rods of the towers or sending manpower and equipment to the towers and lines, so that it will be possible to provide installation of the line signals. That is a time-consuming procedure, as well as difficult, costly, and dangerous, and considering the reasons mentioned above, regarded as prohibitive in several locations.
As it is the knowledge of technicians on the subject, disconnecting high tension lines to install signalization spheres is becoming more difficult every day due to power shortage, as most circuits operate within their limits and an unscheduled disconnection could cause a general overload in all circuits, which could induce a blackout of national proportions.
In light of the problems presented, new alternative techniques have been developed in order to make it possible the operation with the circuits connected, working with live lines, avoiding large power block breaks for consumers.
Basically, three techniques are known so far for the installation of signalization spheres in transmission lines. Those are, the use of a sliding chair on the lightning rod cable, the lowering of lightning rod cables until reaching the phases and the use of helicopters.
After several fatal accidents, all power companies are abrogating the use of the sliding chair technique or any other technique for which the electrician must walk along the lightning rod cable. The cable sometimes would break during the walk, as line electricians had no way to accurately assess lightning rod cable conditions.
Nowadays, although the lowering of lightning rod cables until reaching the phases and the helicopter techniques are being used, the use of signalization sphere installation by means of helicopters, even if perfect weather and wind conditions, is becoming the best option. Even though the costs are relatively high, the cable lowering technique bears an additional disadvantage, that is, the necessary disconnection of circuits.
There is thus the need to provide installation of signalization spheres, unmanned and movable that, by means of remote control, will make it possible for the installation of signalization spheres on transmission line lightning rod cables, as well as the sweeping of the same for maintenance purposes, with the line connected.
With a view to solving the problems previously listed, in accordance with a first embodiment of the present invention, an unmanned device, movable and activated by radio control is provided; developed for the installation of signalization spheres and the checking of lightning rod cable conditions, including a structure of support which consists of two equidistant and parallel bases, connected by axial segments that serve as supports for the activation engines, respectively, a grounding and traction system made of a structure composed of two parallel rods connected by axial segments, showing on their lower end slots for the introduction of a wheel shaft, called a first axial segment, having in its middle section a threaded rod connected on its lower end to the axial segment of the bases, presenting an upper handle and a spring, a movable fork on the external part of the bases on which projects the feeding movable fork descending and balanced, an ascending vertical structure inverted U-shaped, connected externally to a tilted structure to the front part of the bases, having two bars for receiving by fixation of a tightening and loosening tool and showing on their final section a coupling prism with a square hollow inside.
The present invention still uses a sphere to be installed by helicopters with the purpose to be driven (pushed) to the location of installation and fitted by an unmanned, movable device activated by remote control, including two semi-spheres, one vertical shaft furnished with a tightening eyelet on its upper end connected on the lower part to one of the semi-sphere supports which when connected by a walrus-type connector form a conduit for purposes of lightning bolt system fitting.
Moreover, according to a second embodiment of the present invention, a sphere installation method on energized transmission lines is provided, where it is not necessary for the disconnection of the lines. This method does not use a helicopter-type vehicle, reducing significantly the costs if compared to the methods used nowadays, regardless of wind conditions, nor does it cause any losses to power companies, which would be generated by the break of energy supply. The method, according to the second embodiment of the present invention, comprises the following stages:
Fitting of a signalization sphere through the side span existing between the two semi-spheres on the lightning rod cable, until the lightning rod cable is inside and not fastened to the walrus-type connector, so that the signalization sphere will be ready to be moved without the risk of falling along the lightning rod cable.
Fitting of the device upstream from the signalization sphere. Laying the device on the lightning rod cable that will be in contact with the two activating engines of the installation device. Fitting the wheel in the slot through the shaft notch, so that the device grounding can be made, once the wheel is made of metallic conductive material and all the other components of the device are insulated.
Fitting of the fork on the external part of the bases by means of a pivot, furnished with the feeding system;
Coupling of the vertical shaft eyelet end of the sphere inside the device coupling prism and the fixing of safety cupping-glass.
Activating the device by means of a remote control transmitter activated by activating forward/backward engines, taking it to the appropriate location of the sphere;
Rotating wrench-wise, by means of remote control, in the objective location of the installation of the tightening and loosening tool. The tightening will operate on the vertical shaft end of the sphere providing the closing of the walrus-type connector on the lightening rod cable.